New Zealand

Diet, population structure and breeding of Rattus rattus L. in South Island beech forest

The diet, population structure and breeding of ship rats (Rattus rattus L.) from Fiordland National Park were assessed from measurements and gut sample analysis of 248 rats trapped between March 2009 and March 2010, following a mast beech seedfall. They consumed many lepidopteran larvae but fewer weta and more vegetative plant matter than in other habitats, as well as beech seed. Birds and mice made up only a relatively small proportion of the diet. A lizard was also confirmed as a prey item of R.

Ecology of orange-spotted geckos (Mokopirirakau “Roys Peak”) in Central Otago and Queenstown-Lakes district

New Zealand’s mountainous environments support unique flora and fauna specially adapted to the extreme cold and harsh conditions of the alpine zone. The orange-spotted gecko (Mokopirirakau “Roys Peak”) is a rare undescribed gecko that is currently known only from the alpine zone of Otago. The species was discovered in 1998 and is only known from the Central Otago and Queenstown-Lakes districts, with populations spanning a ~3000 km2 area.

Shared visions: can community conservation projects’ outcomes inform on their likely contributions to national biodiversity goals?

In New Zealand, as in other developed nations, community-led conservation groups work to maintain and restore ecosystems and conserve indigenous biodiversity. These groups receive support in the form of materials, technical advice and funding from central and local government and non-governmental organisations, who are required increasingly to demonstrate delivery of benefits or conservation returns on investments. However, there is little empirical evidence for the objective evaluation of the effectiveness of community-based programmes in achieving national conservation outcomes.

Population dynamics of house mice without mammalian predators and competitors

Mesopredator and competitor release can lead to population increases of invasive house mice (Mus musculus) after larger introduced mammals are controlled or eradicated. In New Zealand, mammal-resistant fences have enabled multi-species mammal eradications in order to protect indigenous species. When house mice are the only mammals remaining in these biodiversity sanctuaries, they may reach a high population density, with potential consequences for their indigenous prey.

Calibrating brushtail possum (Trichosurus vulpecula) occupancy and abundance index estimates from leg-hold traps, wax tags and chew cards in the Department of Conservation’s Biodiversity and Monitoring Reporting System

Abstract: The Department of Conservation has implemented a Biodiversity and Monitoring Reporting System (BMRS) that estimates occupancy rates and relative abundances of introduced brushtail possums (Trichosurus vulpecula) at a representative sample of sites on public conservation land. Leg-hold traps have been used to monitor possums in the BMRS, but wax tags and chew cards have logistical and financial advantages over traps.

Compliance with biodiversity compensation on New Zealand’s public conservation lands

This article assesses compliance with biodiversity compensation on New Zealand’s conservation land. Of the 261 Department of Conservation (DOC) concessions for commercial activity searched, only about 15% included compensation provisions. A sample of 20 concessions of that 15% suggests 68% achieve full compliance. Our results suggest compliance is influenced by factors such as habitat and activity type, protected area category, and whether a concession holder has pending concessions and/or renewals. Inconsistencies in compliance monitoring, enforcement, and reporting merit attention.

Preliminary assessment of the foraging behaviour and population dynamics of a cryptic population of the endangered New Zealand sea lion

The endangered New Zealand sea lion (Phocarctos hookeri) has recently been confirmed as breeding on Stewart Island/Rakiura, southern New Zealand. This area is thought to have the largest number of sea lion pups born outside of the New Zealand subantarctics. However, the sparse distribution and cryptic behaviour of this population means known human threats and their effects on the population will be difficult to determine, limiting conservation priority setting and management.

How elevation affects ship rat (Rattus rattus) capture patterns, Mt Misery, New Zealand

There is a lack of information about how elevation affects the distribution of ship rats in New Zealand. In this study, ship rats (Rattus rattus) were captured in traps set along a 2 km elevational transect (455–1585 m a.s.l.) in beech (Nothofagaceae) forest and adjacent alpine tussock at Mt Misery, in Nelson Lakes National Park, from 1974 to 1993. A total of 118 rats were captured.

Assessing and comparing population densities and indices of skinks under three predator management regimes

Introduced mammalian predators threaten populations of endemic New Zealand skinks. Their effects on skink populations have been not often quantified on the mainland and are known primarily from skink population increases on islands from which mammals have been eradicated. Estimating skink population density with capture–recapture trapping is time-consuming and costly. Counting skinks in artificial retreats in specific weather conditions may be a useful and relatively quick way to index population density, but needs calibration for different habitats and species.

Tracking a small cryptic amphibian with fluorescent powders

The study of amphibian spatial behaviour provides key information for species conservation. Most commonly used techniques to track amphibians are either unsuitable for small species or fail to give sufficiently fine-resolution data of habitat use. We report on the use of non-toxic fluorescent powders to track the fine-scale movement of a threatened New Zealand frog, Leiopelma pakeka.